THE RATE OF DISCOUNT AND THE PRESERVATION OF NATURAL ENVIRONMENTS

This paper examines the relationship between the rate of discount and the the optimal level of permanently preserved natural environments. A lower rate of discount increases the demand for both preserved environments and capital accumulation. The greater demand for capital indirectly increases the demand for the productive resource inputs found within the natural environments thereby reducing the level of preservation. This indirect effect outweighs the direct effect of the rate of discount on the level of preservation if the elasticity of output with respect to capital is greater that the elasticity of output with respect to the resource input. In general, the asymptotic values of the output elasticities depend upon the rate of discount and so there can be a nonmonotonic relationship between the rate of discount and the optimal level of permanently preserved natural environments.     

NONMALLEABLE CAPITAL AND EFFICIENT ALLOCATION OF A NONRENEWABLE RESOURCE

Using a discrete-time model with nonmallable and durable capital embodied in a two-period recovery profile, we determine the efficient allocation of a nonrenewable resource and compare it with the corresponding Hotelling allocation for which capital is malleable. Depending on the recovery profile, efficient prices can rise strictly monotonically over time, rise in a stairwise fashion or rise in a sawtooth fashion around a rising price trend. Except for the sawtooth rise, this price behavior requires faster exhaustion than when capital is malleable, implying that the nonmalleability and durability of capital should not be ignored in nonrenewable resource models.     

资本配置视角下财产保险公司承保决策分析

探讨了产险公司在资本和收益双重约束条件下的承保决策问题．首先,从保险理论和实践的角度选择了TVaR资本配置方法,然后构造综合资本、收益双重因素的承保决策模型并进行了实证分析,结论显示从资本的角度进行承保决策是可行的．     

THE PROBLEM OF NONMALLEABLE CAPITAL REVISITED; A STUDY OF THE PACIFIC HALIBUT FISHERY

It has been suggested in the literature on commercial fisheries that fishing capital may be nonmalleable, i.e., not easily moved from one fleet to another, and that the socially optimal rate of capitalization of boats may depend on the degree of malleability (irreversibility) of the fishing fleet. To find out how irreversibility affects optimal regulation, two of the many possible regulatory tools, unallocated quotas and catch taxes, are examined. These optimal policies are derived, alternatively assuming malleable and nonmalleable fishing capital. Using a simulation of the Pacific halibut fishery, the results obtainable through catch quotas are shown to be inferior to those obtainable through taxes, but that the degree of malleability of capital has a surprisingly small impact on policy. A sensitivity analysis is performed, rerunning these simulations over a variety of parameter values. The previous results are largely borne out.     

两部门内生增长模型中财政政策的短期分析

在一个两部门内生增长模型中,讨论政府财政政策变化对居民消费,资本积累以及经济增长的长期影响和短期影响.发现在短期内,政府增加资本收入税不仅可以增加居民消费,而且可以刺激人力资本积累,从而刺激短期经济增长.但是政府财政政策改变对长期经济增长不产生影响,而且资本收入税会降低长期的消费水平和资本存量.另外,从经济增长形态和消费者福利两个角度讨论了资本收入税的无效性.     

THE CONVERSE OF HARTWICK'S RULE AND UNIQUENESS OF THE SUSTAINABLE PATH

ABSTRACT. We provide a constructive proof of the converse of Hartwick's rule for a generalization of Solow's model with one capital good and one exhaustible resource. We also show that the sustainable path is unique.     

动态环境约束下企业的资本积累

本文讨论动态环境约束下企业的动态投资行为,拓广了文献[4]的结果.为了使讨论的问题更符合实际情况,本文假设政府设定的污染排放上限是与企业的规模大小有关,即假设污染排放上限是生产资本的函数,讨论动态环境约束下企业的最佳动态投资行为,并为政府制定污染排放政策提供依据.     

政府花费改变对经济影响的理论分析

本文采用无限期内生时间偏好率模型,研究了政府花费对经济的影响.指出长期的政府花费增加可以使资本存量水平上升,消费水平下降和债券持有量上升;同时,短期分析表明政府花费增加可以减少初始投资率,增加政府债务率水平;但短期的政府花费增加同样导致资本存量水平上升,消费水平下降和债务水平的增加.     

基于模糊集理论的铁路建设项目融资方案综合后评价

铁路建设项目融资方案的优劣决定了项目建设的风险和效益.本文首次提出并明确了铁路建设项目融资方案后评价的概念,指出铁路建设项目融资方案后评价包括投入总资金后评价、资金结构后评价、融资成本后评价、融资风险后评价和资金使用计划后评价五项内容,给出了基于模糊集理论的铁路建设项目融资方案综合后评价的模糊综合评价模型,并通过实例验证了模型的实用性和可操作性,为后评价时点对已运营的铁路建设项目融资方案优劣评价提供了一种简单、科学的综合评价方法.     

LONG-RUN TIMBER SUPPLY: PRICE ELASTICITY,INVENTORY ELASTICITY,AND THE USE OF CAPITAL IN TIMBER PRODUCTION

Timber production requires substantially more capital per unit output than does virtually any other economic enterprise. The quantity of capital deployed depends primarily on the rotation length and the output price for timber. In a long-run timber supply model this gives rise to a “backward bending” supply curve. This paper summarizes a long-run model of timber supply, and computes the associated price and inventory elasticities. The role of capital in timber production is explored through a continuous-time formulation of the usual Faustmann point-input/point-output model. The theoretical results are illustrated through an example based on loblolly pine yields for the U.S. South.     

OPTIMAL INVESTMENT IN THE PROTECTION OF A VULNERABLE BIOLOGICAL RESOURCE

It is assumed that the probability of destruction of a biological asset by natural hazards can be reduced through investment in protection. Specifically a model, in which the hazard rate depends on both the age of the asset and the accumulated invested protection capital, is assumed. The protection capital depreciates through time and its effectiveness in reducing the hazard rate is subject to diminishing returns. It is shown how the investment schedule to maximize the expected net present value of the asset can be determined using the methods of deterministic optimal control, with the survival probability regarded as a state variable. The optimal investment pattern involves “bang-bang-singular” control. A numerical scheme for determining jointly the optimal investment policy and the optimal harvest (or replacement) age is outlined and a numerical example involving forest fire protection is given.     

THE DYNAMICS OF FERTILITY IN C-K MODEL WITH ENDOGENOUS FERTILITY

lhtroduCtlonThe relatloDshlp bet W6W6en the economic gr OWOWth and population growth Is the one of mostimportant problems In the economic growth theorem．In the empirical analyses,the level offertility and the level ofincomeper caplta Is one of*the strongest observably negative correl砒ions,In cross－country dataIS]．Constructing a mathematical model to confirm the empirical indingsIs a m叼or method In thetheoretical study、BeckerI6];GalorI7]and TaTamuraW use OLG modelto discuss this…     

MODELS FOR THE EFFECT OF HIGH SPEED WIND ON THE DEPLETION OF FERTILE TOPSOIL

ABSTRACT. In this paper a mathematical model is proposed and analyzed to study the effect of high speed wind on the depletion of fertile topsoil depth and crop yield. The system is modeled by considering a Cobb‐Douglas production function which depends on depreciating capital stock, a labor force and depth of fertile topsoil. A model to conserve the depth of fertile topsoil and to control the high speed wind is also presented.     

CreditRisk+模型下商业银行经济资本配置研究

对金融资产风险的度量与经济资本的分配应该体现分散化效应,传统的V aR方式不能保证分散化效应的次可加性.本文讨论了基于T a ilV aR这一新的风险度量与经济资本分配标准,并在违约率均值不变情况下,对C red itR isk+模型下的商业银行经济资本分配进行了实证分析.     

我国民间资本投资模型及其实证研究

首先对西方国家投资函数模型进行了综述,在分析这些模型与我国实际情况的基础上建立我国民间投资函数模型,然后运用该模型对我国民间投资进行实证分析。结果表明：本文提出的模型不仅可行而且其预测误差比普通线性回归模型预测误差小得多。     

风险资本的组合投资最优化模型研究

利用委托代理理论建立了风险资本的组合投资最优化模型,通过该模型给出了项目数和收益分配比例的最优解,并分析了组合投资的项目数和收益分配比例对风险投资家和企业家努力水平的影响。     

公共资本对产出及私人资本的动态冲击效应研究

估算了我国总的资本存量和公共资本存量,并从资本存量的角度基于结构向量自回归模型(SVAR)研究了公共资本对私人资本和产出的动态影响.通过实证研究得出以下结论:1)在我国公共资本对私人资本具有先"挤入"后"挤出"的效应.给公共资本一个百分点的冲击,在第'三年使得私人资本增加0.5个百分点.2)产出对公共资本冲击的响应更加快速和直接,给公共资本一个百分点的冲击会使得产出在第2期时增长0.8个百分点,但是这种正的响应会逐渐减弱,并在第6期后不再显著.3)方差分解的结果表明,私人资本对产出的贡献率要大于公共资本对产出的贡献率,私人资本对产出贡献率的最大值为61%,而公共资本对产出贡献率的最大值为28%.     

THE ECONOMICS OF DEFICIT IRRIGATION

Abstract Natural resource economists have paid great attention to irrigation water allocations among competing users. However, the intrauser allocation problem is greatly understudied. As irrigation becomes increasingly capital‐intensive, inefficient within‐field allocation and ill‐designed water‐conservation policy can bring considerable value loss to the water resource. We offer a comprehensive treatment of the economic problem of the intrauser allocation of a limited amount of irrigation water. A framework is provided for determining optimal irrigation intensity and extensity in both static and dynamic settings. An empirical application in West Texas cotton production demonstrates model implementation and offers new insights into the water‐saving potential of government‐sponsored cost‐share programs for promoting high‐efficiency irrigation adoption.     

企业与银行交易关系动态模型分析

本文采用动态分析的方法,分析介绍企业融资与以银行为代表的金融机构可能发生的交易关系,论述了以利益最大化为目标的银企双方在贷借活动中可以通过建立相互信赖的长期交易契约未达到节约投资资金使用成本的一个理论依据．指出了企业“名声”所具有的经济价值能减少经济活动中的机会主义行为,银行的“审查能力”能挽救陷入流动性资金不足的企业免于破产的作用．分析的结果可能会对银行商业化、企业现代化及投资管理决策提供一个参考．     

人力资本、自然资本与最优经济增长要素分析

通过把人力资本、自然资本与社会生产总量联系起来 ,由消费物资多少、获得知识多少及自然资本存量大小这三因素来确定效用 ,提供了物质、人力和自然资本三种重要资产增长的模型框架 ,得到了经济的消费增长率、均衡时各种资本的增长率之间的关系和实现最优经济增长的控制策略 .